One key component of any computer system is a device, (such as a disc drive) to store data. The most basic parts of a disc drive are an information storage disc that is rotated, an actuator that moves a read/write head to various locations over the substantially concentric data tracks of a disc, and electrical circuitry used for encoding data so that the data can be successfully retrieved and written to the disc surface. A microprocessor controls most of the operations of the disc drive including passing requested data read by the transducer to the computer system and receiving data from the computer system for storage on the disc.
A problem associated with disc drives is resonance or vibrations at certain frequencies, which causes the read/write head to move off a designated data track. In other words, if there is even a slight vibration, the read/write head may move away from the center of the designated data track during a track following operation, causing data to be misread or a failure to properly write data. One source of vibration is airflow generated by the rotating discs, which excites head suspensions, which in turn cause the read/write head to vibrate. The vibration causes run-out, i.e., an off-track motion. Off-track motion becomes more acute as the density of tracks increases, because the suspensions and heads become less tolerant of vibration induced movement.
As such, challenges remain and a need persists for improvements in methods and apparatus to reduce vibrations in the suspension.